The Castle of Chora or Great Castle or Paleochora is one of the most famous attractions in Kalymnos. It is situated in the place where ancient Pothia once resided and it is considered as the medieval capital of Kalymnos. The castle takes its final form in 1495 and it is inhabited continuously until 1812 .

Midway between Chora and Pothia you will find the Pera Castle or Castle of Chrisocheria, which is one of the most famous sights in the island. Situated at a strategic point, on the top of a natural hill, this castle helped Kalymnians to easily monitor Chora and Pothia.

The natural division of the Kastelli hill into two different levels was wonderfully exploited by the Kalymnians, who built a Byzantine fortress in this beautiful area in order to control the sea passage between Kalymnos and Telendos.

In Kefalas cave you will be impressed by the imposing, 103 meters long, hallway with the huge stalactites and stalagmites. You will also be able to see traces of the worship of Zeus, which is the reason why the cave bears the alternative name 'Cave of Zeus'.

The Stimenia cave is in the northeast side of Vathys Valley, in St. Nicholas region. Not too far from there, in the northwest side of the valley, there are two more caves, the findings of which indicate their residential use in the distant past.

This is a private museum, a life's work of Valsamidis brothers, who were born and live in Kalymnos. Their love for the sea and the willingness to share its joys and wealth with other people, lead them build this museum with enormous personal effort and enthusiasm. The result of their work will impress you.

The Maritime Museum of Kalymnos was founded in 1994. It presents the naval tradition, history and methods of the sponge catching, along with many artifacts from ancient shipwrecks. In its four rooms you will see objects related to the profession of sponge catching and sponge processing.